Human blood vessels may become occluded or blocked by plaque, thrombi, or other material that reduce the blood carrying capacity of the vessel. Should the blockage occur at a critical place in the circulatory system, serious injury or death may result. Medical intervention can be performed when such an occlusion is detected.
Several procedures are now used to open these occluded vessels, including angioplasty, atherectomy, and stenting. Angioplasty is a well known procedure that uses an inflatable balloon to dilate the occlusion. Atherectomy involves removing the matter occluding the vessel through one of a variety of means, and the process may sometimes be repeated until a sufficient amount of material has been removed to restore blood flow to an acceptable level. Stenting involves temporarily or permanently implanting a substantially cylindrical tube or mesh sleeve into the occluded area of a vessel to radially open the lumen of the vessel. During any of these procedures, material may be separated from the wall of the blood vessel. This separated material can enter the bloodstream, and may be large enough to occlude smaller downstream blood vessels, potentially blocking blood flow to tissue. Intravascular filters are commonly used to capture this separated material during the procedure.
However, it is possible to dislodge some of this material during the placement or introduction of the devices used in the procedure. Therefore, there exists a need to improve operation of the devices during the insertion process.